Myocarditis can be caused by a number of different conditions. The most common cause is infection of the heart muscle by a virus. The virus causes the initial heart muscle inflammation. After the initial viral infection subsides, the body's immune system continues to inflict inflammatory damage on the heart muscles, prolonging the myocarditis, a process termed autoimmunity. Other causes of myocarditis include such as a disease called sarcoidosis, various autoimmune diseases such as systemic lupus, and certain drugs.
Myocarditis, viral: Inflammation of the muscles in the walls of the heart due to a viral infection. Among the offenders are dozen of different common viruses, including the adenovirus, coxsackievirus, poliovirus, echoviruses, and influenza viruses. Destruction of the heart muscle cells may lead to dilated cardiomyopathy and heart failure. See also: Myocarditis.
(2) Myocarditis is an inflammatory condition involving the myocardium (heart muscle).